论文标题
$ \ sqrt {s _ {\ mathrm {nn}}} $ = 5.02 tev tev
Anisotropic flow and flow fluctuations of identified hadrons in Pb$-$Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
论文作者
论文摘要
$π^\ pm $，$ {\ rm k}^\ pm $，p+$ \ overline {\ rm p} $，$ {\ rm k_ {s}^0} $，$+$λ$+$+$+$+$+$ \ \ $ \ $ \ $ \ $ \ $ \ $，$，$，$，$，$，$，$，$，$，$，$，$，$，$，$，$，$，$，$，$，$，$，$，$，$，$， $Ω^ - $+$ $ω^+$使用pb $ - $ pb碰撞中的多片累积物，$ \ sqrt {s _ {\ rm nn}} $ = 5.02 tev。以两种（$ v_2 \ {2 \} $）和四粒子累积物（$ v_2 \ {4 \} $）获得的结果显示为横向动量的函数，$ p _ {\ rm t} $，用于各种冲突中心间隔。将$ v_2 \ {2 \} $和$ v_2 \ {4 \} $的数据组合在一起，也使我们能够报告平均椭圆流，椭圆流的波动和相对椭圆流动的第一个测量值，以使各种强子物种的相对椭圆流动波动。这些可观察的物质探测了初始状态下的事件偏心率波动，以及扩展的夸克 - 胶原等离子体的动态演化的贡献。以前的$ p _ {\ rm t} $ - 具有两个粒子相关性的识别的载体的特征特征 - 即在低$ p _ {\ rm t} $下的质量订购，以$ p _ { $ v_2 \ {2 \} $和$ v_2 \ {4 \} $的四粒子相关和组合。另外，观察到流动波动的粒子物种依赖性，这可能表明最终状态的耐药性相互作用具有显着贡献。实验测量和COLBT模型计算之间的比较，结合了流体动力学，夸克结合和喷气片段化的各种物理过程，这说明了它们对宽$ p _ {\ rm t} $范围的重要性。
The first measurements of elliptic flow of $π^\pm$, ${\rm K}^\pm$, p+$\overline{\rm p}$, ${\rm K_{S}^0}$, $Λ$+$\overlineΛ$, $ϕ$, $Ξ^-$+$Ξ^+$, and $Ω^-$+$Ω^+$ using multiparticle cumulants in Pb$-$Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV are presented. Results obtained with two- ($v_2\{2\}$) and four-particle cumulants ($v_2\{4\}$) are shown as a function of transverse momentum, $p_{\rm T}$, for various collision centrality intervals. Combining the data for both $v_2\{2\}$ and $v_2\{4\}$ also allows us to report the first measurements of the mean elliptic flow, elliptic flow fluctuations, and relative elliptic flow fluctuations for various hadron species. These observables probe the event-by-event eccentricity fluctuations in the initial state and the contributions from the dynamic evolution of the expanding quark-gluon plasma. The characteristic features observed in previous $p_{\rm T}$-differential anisotropic flow measurements for identified hadrons with two-particle correlations, namely the mass ordering at low $p_{\rm T}$ and the approximate scaling with the number of constituent quarks at intermediate $p_{\rm T}$, are similarly present in the four-particle correlations and the combinations of $v_2\{2\}$ and $v_2\{4\}$. In addition, a particle species dependence of flow fluctuations is observed that could indicate a significant contribution from final state hadronic interactions. The comparison between experimental measurements and CoLBT model calculations, which combine the various physics processes of hydrodynamics, quark coalescence, and jet fragmentation, illustrates their importance over a wide $p_{\rm T}$ range.
